Re: Highlighting cursor for char before

[Eli Zaretskii <eliz@gnu.org>]

> From: Alexandre Garreau <galex-713@galex-713.eu>
> Cc: Eli Zaretskii <eliz@gnu.org>
> Date: Wed, 27 Oct 2021 16:44:35 +0200
> 
> > Most importantly, it is entirely non-trivial to determine which is the
> > "character before", in bidirectional text.  Look at the code of
> > move-point-visually to see how non-trivial it is to solve a similar,
> > but different problem: which character is the one to the right or to
> > the left of the current one.
> 
> I do a distinction in phrasing between “before” and “to the left”, and 
> “after” and “to the right”, for semantical and confusion-avoiding purpose.  
> So, if I understand correctly (and I always though to understand that but 
> maybe the terminology I don’t): the “character before” is trivial but 
> what’s not trivial is “the character at left/right”, right?  I mean, 
> before/after, for me, is only a matter of time and/or order in the buffer 
> (most near to beginning = before, most near to end = after), and that 
> stays linear and context-independent (like if I only use C-b and C-f, 
> which follows not spatial direction but semantical order of chars as 
> stored in the buffer), while only the visual thing is…
> 
> Do we understand each other correctly?

About what?  You ask so many questions, and OTOH say so little apart
of the questions, that I no longer understand what you are talking
about.

> Ok that was precisely what I wanted to know (especially as I totally trust 
> your opinion for that matter, as a beginning (is that treated in xdisp.c 
> as well?)), except given the misunderstandment above I’m unsure you 
> correctly understood what I meant… I meant the precise opposite of what 
> the block cursor currently does… is that so complex?

It is complex, yes.  That's what I tried to explain.

And I don't think it makes sense to display the cursor on the
character before point, because it will be terrible in bidirectional
context.  Are there any other editors that show the cursor that way?
But if someone wants such a feature as an option, why not?